Home > Press > GeneSegues and Collaborators at University of Minnesota Publish New Research Showing Targeted Nanocapsule Delivery of Plasmid DNA for Long Term Treatment of Hemophilia in Mice

Abstract:
GeneSegues, Inc., a biopharmaceutical company developing and commercializing novel nanocapsule-based drug delivery technology, announced today a publication in the Journal of Clinical Investigation demonstrating that systemic administration of plasmid DNA in liver-targeted, non-viral nanocapsules resulted in complete and long term phenotypic correction of hemophilia A in a mouse model.

GeneSegues and Collaborators at University of Minnesota Publish New Research Showing Targeted Nanocapsule Delivery of Plasmid DNA for Long Term Treatment of Hemophilia in Mice

Chaska, MN | Posted on June 9th, 2009

The work is the result of collaborative studies between GeneSegues and the laboratory of Clifford Steer, M.D., Professor of Medicine, University of Minnesota, and was supported by grants from the National Heart, Lung, and Blood Institute, the National Institute of Diabetes and Digestive and Kidney Diseases, and the Department of Defense.

"Hemophilia A is an X-linked congenital bleeding disorder caused by deficiency of coagulation Factor VIII, affecting more than one-half million males worldwide," said lead author Betsy Kren, Ph.D., Assistant Professor of Medicine, University of Minnesota. "Cell-specific delivery of DNA plasmid to the endogenous production site for Factor VIII, to restore Factor VIII levels for an extended period without the development of anti-Factor VIII antibodies, could contribute significantly to a more effective treatment of hemophilia A. To date, no non-viral approach has been identified that is capable of achieving such results. We believe these findings may represent a major advance in the field of gene therapy, and are very encouraged by the results published today with GeneSegues."

The work described in the publication (Kren et al., Journal of Clinical Investigation,advance online publication 8 June 2009; doi: 10.1172/JCI34332; available at www.jci.org/articles/view/34332), uses the transgene plasmid ‘Sleeping Beauty', expressing B-domain deleted canine Factor VIII and encapsulated in sub-50 nanometer capsules with a hyaluronan ligand shell targeting specifically to liver sinusoidal endothelial cells, to restore Factor VIII levels in Factor VIII knockout mice. The animals were monitored for clotting time by measuring activated partial thromboplastin times (aPTT) over a period of 50 weeks. Single-dose intravenous delivery of the encapsulated plasmid resulted in improvement of aPTT of the treated mice to levels statistically equivalent to wild-type controls through the 50-week study period, while all untreated controls died before the end of the study. Importantly, results showed that the encapsulated plasmid did not activate anti-Factor VIII antibodies.

"Our collaboration with Drs. Steer and Kren and their colleagues has been very productive, and we are pleased to have the opportunity to work with a leading group of researchers in this area," said co-author Gretchen Unger, Ph.D., President of GeneSegues. "We are very encouraged by the results of this hemophilia work, as well as complementary work with reporter genes showing that specific uptake by different liver cell-types corresponds with the applicable capsule targeting ligand. New approaches to gene therapy using nonviral delivery systems may pave the way for novel disease-modifying medicines for hemophilia as well as other diseases of the liver."

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About GeneSeguesGeneSegues is a privately-held biopharmaceutical company focused on developing and commercializing novel nanocapsule-based drug delivery technology for DNA and RNA-based therapeutics. The company’s sub-50 nanometer (“s50”) capsule technology is unique in the capability to co-opt nondegradative pathways into the target cell, avoiding intracellular drug degradation that has thus far thwarted commercialization of DNA/RNA-based therapeutics. GeneSegues has expertise in working with all types of nucleic acid-based drugs including plasmids and single and double-strand RNAi, in tissue culture and animal models. The company has established collaborative relationships with larger drug developers, whereby s50 technology is being used to deliver nucleic acid-based therapeutics to a broad range of targets, via systemic as well as topical administration.